it makes sense because otherwise, if you have to perform such an task and you're not in reach for the server or the server has no keyboard attached, you can't trigger system request keys.

your example does not work because of different problems.

according to this site you have to set "/proc/sys/kernel/sysrq" to something other than 0. you have to search the manuals for the right value. then you are able to echo something into "/proc/sysrq-trigger".

you have to be root for this. "sudo echo SOMETHING > /SOMEWHERE" does not work because of the output redirection ">".

you have to do this like the examples on this site - a full example would be:

After i wrote all this i catched probably another issue of your test :). if you execute for example the "t" sysrq key over an remote session or for example an xterm you can't see the output because sysrq output goes to the "real" console. issue dmesg to see the output!